The Calendar of Allah's Khadur

Prophet sallam wanted the ummah to respond on the day of judgment that oh Allah our Processam has done the job. So he's making them testify and they all testified to this in a khutba. He gave another khutba on the 10th of the Hijjah and he said that verily time has returned to its rightful place as It was on the day that Allah created the heavens and the earth A year is 12 months Four of which are sacred or sacred three of whom are consecutive.